2 wordpress plugins

Hi, i need 2 wordpress plug ins for my website, they're actually pretty simple to do, they won't take a lot of time. The first plugin will randomize comments from my page every time someone refreshes the page but do not repeat comment from the same person twice. and also will let people tag/categorize their own comments. the second plug in, what I want is to Put a Train Followers on my blog, in certain page, when a User register in my page via Tumblr will automatically will be added to a train. the page will show around 50 tumblrs (please leave customizable) and the avatar will be display next to each other and everytime someone rides the train the last blog will disappear we can use wordpress social log in plugin to connect with tumblr so it will reduce the time of your work.